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Isolation of Microstructure in Proton-Irradiated Steels. Topical Report

Description: OAK B188 Isolation of Microstructure in Proton-Irradiated Steels. Topical Report. Component degradation by irradiation is a primary concern in both current reactor systems as well as advanced designs and concepts where the demand for higher efficiency and performance will be considerably greater. In advanced reactor systems, core components will be expected to operate under increasingly hostile (temperature, pressure, radiation flux, dose, etc.) conditions, The current strategy for assessing ra… more
Date: September 1, 2000
Creator: Was, G.S.; Atzmon, M. & Wang, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The role of gamma rays and freely-migrating defects in reactor pressure vessel embrittlement

Description: Gamma ray effects are often neglected when evaluating reactor pressure vessel (RPV) embrittlement. However, recent analyses indicate that in newer style light water reactors, gamma damage can be a substantial fraction of the total displacement damage experienced by the (RPV); ignoring this damage will lead to errors in embrittlement predictions. Furthermore, gamma rays may be more efficient than fast neutrons at producing freely-migrating defects and as such can impact certain embrittlement mec… more
Date: September 1, 1996
Creator: Alexander, D. E. & Rehn, L. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of corotating interaction regions on ULYSSES high energy particles

Description: Since June 1992 the Kiel Electron Telescope on board ULYSSES measures variations of more than 10% in the fluxes of high energy H and He showing a periodicity of about 26 days in coincidence with the passage of corotating interaction regions. (CIR). At low energies MeV protons are accelerated at the shocks of the CIRs. These effects are observed up to high southern latitudes, where the signature of a CIR is no longer visible in plasma or magnetic field data. After passing over the south polar ca… more
Date: September 1, 1995
Creator: Droege, W.; Kunow, H. & Raviart, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mathematical models for volume rendering and neutron transport

Description: This paper reviews several different models for light interaction with volume densities of absorbing, glowing, reflecting, or scattering material. They include absorption only, glow only, glow and absorption combined, single scattering of external illumination, and multiple scattering. The models are derived from differential equations, and illustrated on a data set representing a cloud. They are related to corresponding models in neutron transport. The multiple scattering model uses an efficie… more
Date: September 1, 1994
Creator: Max, N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurements of x-ray spectral flux and intensity distribution of APS/CHESS undulator radiation

Description: Absolute radiation flux and polarization measurements of the APS undulators may have to be made under high thermal loading conditions. A method that may circumvent the high-heat-load problem was tested during a recent APS/CHESS undulator run. The technique makes use of a Si(Li) energy-dispersive detector to measure 5--35 keV x-rays scattered from a well-defined He gas volume at controlled pressure.
Date: September 1, 1994
Creator: Ilinski, P.; Yun, W.; Lai, B.; Gluskin, E. & Cai, Z.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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BEATRIX-II: In situ tritium recovery from Li[sub 2]O and Li[sub 2]ZrO[sub 3] irradiated in a fast neutron flux

Description: The BEATRIX-II irradiation experiment was an in situ, fast neutron, tritium release experiment to evaluate the performance of ceramic fusion solid breeders at extended burnups. The experiment consisted of two sequential irradiations: Phase I for 300 EFPD and Phase II for 200 EFPD that resulted in lithium burnups from 4[endash]6%. Thin-walled Li[sub 2]O ring specimens capable of temperature changes were irradiated in both Phase I and Phase II. Temperature changes were also used to determine the … more
Date: September 1, 1992
Creator: Slagle, O. D.; Hollenberg, G. W.; Kurasawa, T. & Verrall, R. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Conceptual design summary

Description: The Advanced Neutron Source (ANS) is a new basic and applied research facility based on a powerful steady-state research reactor that provides beams of neutrons for measurements and experiments in the fields of materials science and engineering, biology, chemistry, materials analysis, and nuclear science. The useful neutron flux for these experiments will be at least five times, and in some cases twenty times, more than is available at the world's best existing facilities. In addition, ANS will… more
Date: September 1, 1992
Creator: Peretz, F. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DNA Radiation Environments Program - Spring 1990 2-meter box experiments and analyses

Description: This report summarizes the Spring 1990 2-m Box Experiments performed at the Army Pulse Radiation Facility (APRF) at Aberdeen Proving Ground, Maryland. These studies were sponsored by the Defense Nuclear Agency (DNA) under the Radiation Environments Program to obtain measured data for benchmarking the Adjoint Monte Carlo Code System, MASH, Version 1.0. MASH was developed as the Department of Defense and NATO code system for calculating neutron and gamma-ray radiation fields and shielding protect… more
Date: September 1, 1992
Creator: Santoro, R. T & Whitaker, S. Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DNA Radiation Environments Program - Spring 1990 2-meter box experiments and analyses

Description: This report summarizes the Spring 1990 2-m Box Experiments performed at the Army Pulse Radiation Facility (APRF) at Aberdeen Proving Ground, Maryland. These studies were sponsored by the Defense Nuclear Agency (DNA) under the Radiation Environments Program to obtain measured data for benchmarking the Adjoint Monte Carlo Code System, MASH, Version 1.0. MASH was developed as the Department of Defense and NATO code system for calculating neutron and gamma-ray radiation fields and shielding protect… more
Date: September 1, 1992
Creator: Santoro, R. T. & Whitaker, S. Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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1DB, a one-dimensional diffusion code for nuclear reactor analysis

Description: 1DB is a multipurpose, one-dimensional (plane, cylinder, sphere) diffusion theory code for use in reactor analysis. The code is designed to do the following: To compute k{sub eff} and perform criticality searches on time absorption, reactor composition, reactor dimensions, and buckling by means of either a flux or an adjoint model; to compute collapsed microscopic and macroscopic cross sections averaged over the spectrum in any specified zone; to compute resonance-shielded cross sections using … more
Date: September 1, 1991
Creator: Little, W.W. Jr. (Pacific Northwest Lab., Richland, WA (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A model for the prediction of Nb sub 3 Sn critical current as a function of field, temperature, strain, and radiation damage

Description: Conductors designed for fusion machines must operate at high fields, under large mechanical loads, and in a high neutron flux. Present designs favor the use of Nb{sub 3}Sn with force-cooling by supercritical helium to extract large nuclear and ac loss heat loads. Consequently, the magnet designer must have a good knowledge of the critical current of the superconductor as a function of field, strain, temperature, and radiation damage. Expanding on work by Hampshire, et al. and Ekin, combined wit… more
Date: September 21, 1990
Creator: Summers, L. T.; Guinan, M. W.; Miller, J. R. & Hahn, P. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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(Reactor dosimetry)

Description: The lead in most aspects of research reactor design and use passed from the USA about 15 years ago, soon after the construction of the HFIR and HFBR. The Europeans have consistently upgraded and improved their existing facilities and have built new ones including the HFR at Grenoble and ORPHEE at Saclay. They studied ultra-high flux concepts ({approximately}10{sup 20}/m{sup {minus}2}{center dot}s{sup {minus}1}) about 10 years ago, and are in the design phase of a new, highly efficient medium fl… more
Date: September 13, 1990
Creator: West, C.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Breeding rate measurements in solid fusion blankets with metallic lithium samples

Description: Measurement of the local breeding rate in a large assembly of fusion blanket candidate materials, irradiated by a fusion neutron source, serves the dual purpose of blanket design support and, perhaps more importantly, calculational method and cross section library testing. In this report, we present technical details of a measurement scheme based on deployment of encapsulated lithium metal samples and subsequent thermal digestion of the samples in a metered carrier hydrogen stream, conversion t… more
Date: September 1, 1990
Creator: Porges, K. G. & Bretscher, M. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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US--ITER activation analysis

Description: Activation analysis has been made for the US ITER design. The radioactivity and the decay heat have been calculated, during operation and after shutdown for the two ITER phases, the Physics Phase and the Technology Phase. The Physics Phase operates about 24 full power days (FPDs) at fusion power level of 1100 MW and the Technology Phase has 860 MW fusion power and operates for about 1360 FPDs. The point-wise gamma sources have been calculated everywhere in the reactor at several times after shu… more
Date: September 1, 1990
Creator: Attaya, H.; Gohar, Y. & Smith, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A safety assessment of the use of graphite in nuclear reactors licensed by the US NRC

Description: This report reviews existing literature and knowledge on graphite burning and on stored energy accumulation and releases in order to assess what role, if any, a stored energy release can have in initiating or contributing to hypothetical graphite burning scenarios in research reactors. It also addresses the question of graphite ignition and self-sustained combustion in the event of a loss-of-coolant accident (LOCA). The conditions necessary to initiate and maintain graphite burning are summariz… more
Date: September 1, 1987
Creator: Schweitzer, D.G.; Gurinsky, D.H.; Kaplan, E. & Sastre, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cross Section Evaluation Working Group benchmark specifications. Volume 2. Supplement

Description: Neutron and photon flux spectra have been measured and calculated for the case of neutrons produced by D-T reactions streaming through a cylindrical iron duct surrounded by concrete. Measurements and calculations have also been obtained when the iron duct is partially filled by a laminated stainless steel and borated polyethylene shadow bar. Schematic diagrams of the experimental apparatus is included.
Date: September 1, 1986
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Progress on the IPNS Enriched Uranium Booster Target

Description: We describe the Enriched Uranium Booster Target designed for use in Argonne's Intense Pulsed Neutron Source. This report contains a general description of the system, and descriptions of the thermal-hydraulic and loss-of-coolant accident analyses, of the neutronic, criticality and power density calculations, of the assessment of radiation and thermal cycling growth, and of the disk fabrication methods. We also describe the calculations of radionuclide buildup and the related hazards analysis an… more
Date: September 1, 1986
Creator: Knox, A. E.; Carpenter, J. M.; Bailey, J. L.; Armani, R. J.; Blomquist, R. N.; Brown, B. S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermal problems on high flux beam lines

Description: Wiggler and undulator magnets can provide very intense photon flux densities to beam line components. This paper addresses some thermal/materials consequences due to such impingement. The LBL/Exxon/SSRL hybrid-wiggler Beam Line VI now nearing operation will be able to provide up to approx. 7 kW of total photon power at planned SPEAR operating conditions. The first masks are located at 6.5 meters from the source and may receive a peak power density (transverse to the beam) exceeding 20 kW/cm/sup… more
Date: September 1, 1983
Creator: Avery, R.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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COROPT heterogeneous flux model

Description: The PHYSICS module of COROPT calculates the power and flux distributions, power fractions, required fissile enrichment, and fuel mass balances. Sufficiently accurate data are clearly necessary for the results of the thermal hydraulic and fuel pin and assembly performance analysis to be acceptable. The smooth flux and power distribution model developed for the homogeneous core COROPT application has been shown to be accurate for homogeneous cores in the range of interest. However, this model and… more
Date: September 1, 1981
Creator: Bailey, H.S. & Alexander, C.N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cosmic-ray-induced radiation environment and dose to man for low-orbit space applications

Description: Neutrons and photons resulting from the interaction of galactic cosmic rays with the material of an orbiting satellite or an orbiting space station at an altitude of some few hundreds of kilometers, and below the level of the radiation belts, have been calculated as a function of geomagnetic latitude and solar activity level. The photon and neutron leakage currents from the top of the atmosphere have been computed. The radiation dose-equivalent rate to an unshielded astronaut has also been calc… more
Date: September 1, 1981
Creator: Sandmeier, H. A.; Hansen, G. E.; Battat, M. E. & O'Brien, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Depth-charge static and time-dependence perturbation/sensitivity system for nuclear reactor core analysis. [LMFBR]

Description: This report provides the background theory, user input, and sample problems required for the efficient application of the DEPTH-CHARGE system - a code block for both static and time-dependence perturbation theory and data sensitivity analyses. The DEPTH-CHARGE system is of modular construction and has been implemented within the VENTURE-BURNER computational system at Oak Ridge National Labortary. The DEPTH-CHARGE system provides, for the first time, a complete generalized first-order perturbati… more
Date: September 1, 1981
Creator: White, J.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of the new GCFR upper and lower plenum flow-through shields

Description: Analysis of the proposed GCFR upper and lower plenum flow-through shields has been performed using both discrete ordinate (DOT) and Monte Carlo (MORSE) methods. Several shields having one change of direction in the coolant path (chevron) and two changes of direction (herringbone) were investigated. The shields were modeled as unit cells with periodic boundary conditions. From plenum fluence calculations and design constraints at the reactor vessel liner, it was determined that all the shield co… more
Date: September 14, 1980
Creator: Cramer, S.N. (Oak Ridge National Lab., TN); Reed, D.A.; Emmett, M.B. & Rouse, C.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Neutron flux measurements around PLT

Description: Using Indium activation foils, the toroidal and poloidal neutron emission patterns were determined for PLT plasmas which include ICRF and neutral beam heating. The activities produced the /sup 115/In (n,n') /sup 115m/In reaction were determined by counting the 336 keV ..gamma.. line of the /sup 115m/In decay. This activation cross section falls just below 2.5 MeV so that the influence of scattered neutrons of degraded energies is reduced. From the magnitude of the activity, the absolute calibra… more
Date: September 1, 1980
Creator: Zankl, G.; Strachan, J.D.; Lewis, R.; Pettus, W. & Schmotzer, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fission cross section for /sup 242m/Am. [0. 01 eV to 20 MeV, neutron flux, fission fragments]

Description: The neutron-induced fission cross section for /sup 242m/Am(152y) was measured at the Livermore 100-MeV electron linac in the neutron energy range of 0.01 eV to 20 MeV. Fission fragments were detected using a hemispherical fission chamber. The neutron flux was measured below 10 keV using lithium glass scintillators. Above 10 keV, the /sup 242m/Am fission cross section was measured relative to the /sup 235/U fission cross section. Below 20 eV, the data were fit with a sum of single-level Breit-Wi… more
Date: September 20, 1978
Creator: Browne, J. C.; Howe, R. E.; Dougan, R. J.; Dupsyk, R. J. & Landrum, J. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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